When civilian journalists - bloggers to you and me - write a new post, they tend to send the link out on Twitter and hope that people will retweet and share it. If that doesn't work, they can try badgering, bullying, bribery and blackmail - but if the readers don't think it's up to scratch, they won't pass it on. You could call it raw news judgment.
Professional journalists pass similar verdicts dozens of times every day. Reporters are bombarded with handouts, emails and phone calls from PR types trying to sell this soap, that survey, and the other view on what some politician said yesterday. Just like the people on Twitter who glance at a link and move on, the reporter needs to be convinced before passing this unsolicited information to a wider public.
Most handouts are just sophisticated junk mail, with commensurate news value. For a start, they invariably present the one-sided view of someone with a vested interest or an axe to grind. On busy news days, they'll be cast into the trash, but in quieter times they may win a second look. This weekend, with little more than a rainy bank holiday and some election fallout vying for news space, news editors will pay slightly more attention to the dangers of drinking tonic water, while PRs worth their salt will time their pitches on how to improve the transport system.
Since none of this is strictly news, a story's chances of appearing in print will rely on how interesting rather than how important it is. And that, of course, is an entirely subjective judgment.
Sadly for the diversity of the press, these judgments are largely made by the same sorts of people. Our national newspaper editors are, with one exception, white men, mostly in their forties and fifties. Backbenches and newsdesks are also still male-dominated, while women continue to be allowed - and I use the word advisedly - their heads predominantly in the features departments. And so, the news agendas have similar threads running across all breeds of paper, a lot of them born of received wisdom rather than genuine belief - a journalistic version of case law, if you like.
One perennial that should have died off 20 years ago still flowers: the housing market. As with all plants, it blooms more profusely when under stress - in this case when there's little else to fill the paper.
I was rebuked in the 1980s for failing to run a house price index story. "House prices are of abiding interest to all our readers," I was told. That might have been true then, but the surveys seemed meaningless, other than to provide dinner party chat fodder: after all, who lived in the 'average' house? In the 80s and 90s, prices were either soaring or plummeting, and there were real differences day to day, not just month to month, with couples either celebrating huge paper profits and dreaming of luxurious retirement or despairing as their biggest asset shrunk before their eyes. People stopped seeing a house as a place to put down roots and build a family and a life, but as a step on a ladder that led to the rainbow with its pot of gold on the side.
That ladder idea still pertains, though these days it has only a couple of rungs leading from living with mum and dad to a modest house via a starter home.
The market has been pretty stable - stagnant might be a better word - for years, but the newspapers' obsession remains undiminished. The same goes for interest rates - or rather for mortgage rates; no one gives a stuff about savers.
On Tuesday The Times splashed on the news that more than a million homebuyers would see their repayments increase by hundreds of pounds a year because a clutch of lenders, including the Halifax with 850,000 borrowers, were raising their variable rates. This would, the report said, add £55 to the monthly cost of an "average" £200,000 mortgage.
There was nothing in this story about what, if anything, was happening to savers' rates - even though there are roughly seven times as many savers as borrowers in this country and millions of pensioners struggling on fixed incomes and dismal annuities. The rates are going up because money is costing more on the wholesale market. It's all about profit - and in the case of the Halifax, getting some dosh back to the taxpayer.
Savers continue to receive a paltry 1 or 2% return on their money. You might read a bit about this in the personal finance pages, but rarely does the issue feature on the news pages. After all, news editors tend to be family men trying to make ends meet as the mortgage goes up. And these young men haven't lived through the era of 10, 12 and 15% interest rates; to them, anything above 4% feels like usury.
And what's happening to property prices? Well, the Nationwide published its April figures today (above) and the Halifax is due to produce its statistics in the next few days - and they're bound to get big play, it being a quiet news weekend. So was I wrong in the 80s? Do they have value? Judge for yourself from the March figures.
The Halifax reported that prices went up 2.2% in March, after a 0.4% fall in February.
Prices in the first three months of the year were 0.6% lower than in the same quarter last year. The average house price in March was £163,803.
The Nationwide reported that prices went down by 1% in March, after a 0.4% increase in February.
First quarter prices were 0.2% up on the same three months of 2011.
The average house price was £163,327.
The Land Registry reported that prices were down by 0.6% in March after an 0.1% increase in February.
The average house price was £160,372.
Do you feel wiser for that? The only vague area of consistency is the average house price. But, as I asked earlier, what is an average house? You are looking at a mean price taking into account castles in Scotland, mews houses in Kensington, semis in Swansea and studio flats in Hull.
Yet still newspapers insist on publishing these statistics - although whether they appear as fillers in the business pages or splashes to the entire paper depends on whether there's anything else to fill the space.
Of course we have to publish unemployment and inflation statistics monthly. But, come on, these house price figures are just another bit of PR junk mail and they should be treated with the scepticism that would be meted out to any other single-interest survey. The very least we can do is to offer our readers the service of researching a little deeper. For example, doesn't it strike you as interesting that Leah Milner in The Times told us on Tuesday that the "average" loan of £200,000 would cost £55 a month more. An average loan of £200,000? When the average house costs £163,000 - and at a time when banks are reluctant to lend more than 80% of its value?
And so to Madeleine. As expected, the McCanns surfaced for the anniversary. And just as no news editor dares shy away from house prices, nor will he risk missing the latest performance from this circus.
Let's be clear on this. Just because it's the anniversary, there is no obligation to run a Madeleine story. Just because the McCanns speak, there is no obligation to record their every utterance. Just because a television programme broadcasts an interview, there is no obligation to reproduce the transcript in print. But we just can't help ourselves, can we?
So, of course, we had two papers splashing on the missing child today, while the Express exercised the utmost restraint and contented itself with a front page picture puff.
Was there any news? Well, Gerry told Lorraine Kelly's television programme that he had never felt as confident as he did now that the mystery would be solved. And Kate said that the younger twins had vowed to find their big sister.
Come again? The twins are seven. They can see how preoccupied their parents are; children of that sort of age are sensitive and eager to please. It's easy to imagine little Sean saying "Don't worry Mummy, if you don't find Madeleine, Amelie and I will keep on looking until we do." Now let's go and play football please.
How much store can we set by such promises? In a family dominated by its absent member? Is this not the sort of placatory stuff you'd expect from a child whose life is overshadowed by an older sister he never knew? When my daughter was that age, she invented her own personal rescue service, Horse Help Need. When we discovered on returning from a trip to France that the back of the new car and all its contents were smothered in spilt washing liquid, she rushed into the house. We hoped she had gone to fetch a mop or cloth. But no, she came galloping out in her Horse Help Need hard hat and badge and went charging round the car promising help without doing anything practical, like helping to unload the sodden holdalls. That's what seven-year-olds do. Their pledges on unending quests are to be taken lightly.
It wouldn't be a proper anniversary, though, without a 'new lead', and today's offering was a taxi driver who claimed to have had Madeleine and four adults in his cab on the night of the disappearance. Now this is an interesting one. "I'm certain it was her," said Antonio Castela, 72. He had picked up the child, three men and a slim blonde woman from a taxi rank in Monte Gordo - about an hour from Praia da Luz, where the McCanns had been staying - and taken them to an hotel two miles away. There they had got into a waiting blue jeep with foreign number plates and driven off. He was sure it was Madeleine because the little girl was wearing pink Eeyore pyjamas and he noticed the mark in her eye - it was the same as one his son had.
Mr Castela had told the police all this at the time, but "I never heard anything from them again. they didn't seem to take me seriously and never questioned me. They simply took down the details and that was it. I'm amazed nobody has ever asked me what I saw that night."
Tut, tut. Those hopeless Portuguese police again. Those lazy coppers who weren't chasing the hundreds of sightings reported in the early days of the hunt.
What do the McCanns make of Mr Castela's story? Their spokesman Clarence Mitchell said: "Mr Castela did absolutely the right thing at the time by reporting his sighting. It is clearly deeply shocking that he now tells us he hasn't been interviewed once by a detective in five years." The whole account would doubtless be scrutinised by the new Met review of the case.
Shocking indeed. Is this the same taxi-driving Mr Castela who told his story to The Sun in 2008? The same Mr Mitchell who then discounted the evidence "primarily because the timings are entirely wrong"?
Yes, the taxi driver story that appeared in the Evening Standard, Express and Star today is almost identical to the one published in The Sun and on the Telegraph and Standard websites four years ago. Then Mr Castelo was quite convinced not only that it was Madeleine sitting on the lap of a rear-seat passenger, "staring straight ahead as though doped", but also that the slim blonde woman was Mrs McCann and that the person in the front passenger seat was Robert Murat - a man whose life was turned upside down as people scattered wild accusations and innuendo willy nilly, with no concern for the consquences.
For heaven's sake. When are we going to get real and do some proper journalism or let well alone?
Thank you for sticking with it to the end. Please do share your thoughts below. And please take a look at the other posts. They are all media related.
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Hello and goodbye to Wapping a personal diary of life inside the fortress in the days before the strike that changed newspapers forever
Out of print a love letter to newspapers in this digital age. Why they don't have to die if we have the will to let them live and thrive
Why local newspapers matter Why we should care about the revolution in the regional press
Missing: an opportunity How the hunt for Madeleine McCann could be turned into a force for good instead of just a festival of mawkish sentimentality
Riding for a fall Does buying a ticket for a jolly day out at the races mean you are fair game for the snobs who sneer and snipe?
Just a pretty face Illustrating the business pages isn't the easiest job in the world, but spare us the celebs who aren't even mentioned in the story
Food for thought a case study in why we should take health advice with a pinch of salt (and a glass of red wine and a helping of roast beef)
The world's gone mad Don Draper returns and the drooling thirtysomethings go into overdrive But does anybody watch the show? (But there is more Whipple in this post!)